JSFiddle - React, Tailwind, and code Playground

HTML

<div class="star-rating-wrap">
    <div class="star-rating">
        <span>123</span>
    </div>
</div>

CSS

.empty
{
    background: red;
    height: 10px;
}

JavaScript

$(function () {
	if(!$('.star-rating').children().length) {
    	$('.star-rating').after('<div class="empty"></div>');
    }
});